The present invention relates to a technique of processing a frame image of an imaging area imaged by a camera, and detecting an imaged object.
Conventionally, there has been proposed an image processing device configured to process a frame image of an imaging area imaged by a camera, and perform detection of an imaged object such as a person, vehicle, or the like and tracking of the detected object (see JP 9-265585 A). The general image processing device of the related art generates a differential image (background differential image) of the frame image of the imaging area imaged by the camera and a background image of the imaging area, a differential image (inter-frame differential image) of the two temporally successive frame images, and the like as shown in JP 9-265585 A, and the like to detect and track the object.
However, in the conventional image processing device, a frequency (clock frequency) of an operation clock of a processor (image processing processor) is fixed. The image processing processor processes the frame image of the imaging area imaged by the camera.
In the image processing processor, the processing speed becomes faster as the frequency of the operation clock becomes higher, and the power consumption increases. The load applied on the image processing processor becomes greater as the number of objects imaged in the frame image becomes larger.
Therefore, the conventional image processing device has defined the frequency of the operation clock of the image processing processor so as to obtain the processing speed required when the number of objects imaged in the frame image is large. Thus, if the number of objects imaged in the frame image is relatively small, the processing speed of the image processing processor becomes faster than necessary, and the power consumption becomes unnecessarily large. Furthermore, since the heat generation amount becomes larger as the power consumption is larger, the lifespan of the image processing processor becomes short.
It is desired to provide a technique capable of efficiently reducing power consumption and extending a lifespan.